A projector including a projection portion projecting an image onto an arbitrary projection area is known in general. Such a projector is disclosed in Japanese Patent Laying-Open No. 9-134135, for example.
In the aforementioned Japanese Patent Laying-Open No. 9-134135, there is disclosed a laser projection display (projector) including a plurality of laser transmitters emitting red (R), green (G) and blue (B) laser beams respectively and a polygonal rotating mirror (projection portion) for horizontally scanning the emitted laser beams. This laser projection display is provided with a plurality of sets of laser transmitters each emitting red (R), green (G) and blue (B) laser beams, in order to improve brightness of laser beams (image) projected on a screen. The laser projection display is so formed that the laser beams emitted from the plurality of sets of laser transmitters respectively are applied concentrically to the same point of the polygonal rotating mirror through a laser beam splitter, a modulator, a photosynthetic optical system and a reflecting mirror etc. Further, the laser projection display is so formed that the laser beams applied to the polygonal rotating mirror are reflected on the surface of the polygonal rotating mirror and thereafter projected onto the screen through a rotating reflection optical system for vertically scanning the laser beams, a condenser lens and a taking lens.